Crank-shaft



(No Model.) 3 Sheets-Sheet 1.

D. A! WOODBURY.

CRANK SHAFT. No. 367,884. Patented Feb. 15, 1887.

(No Model.) 3 Sheefis-Sheet 2.

1). A; WOODBURY.

CRANK SHAFT.

3 Sheets-Sheet 3.

(No Model.)

D. A. WOODBURY.

CRANK SHAFT. No. 357.884. Patented Feb. 15, 1887.

UNITED STATES PATENT OFFICE.

CRANK- SHAFT.

SPBCIPICATION forming part of Letters Patent No,

357.884, dated February 15, 1887.

Application filciMarch 12, 1886. Serial No. 194,953. (No model.)

To all whom 'it may concern.- 7 Be it known that I, DANIEL A.WoonBURY, a citizen of the United States, residing in the city of Rochestelgin the county of Monroe and State of New York, have invented a new and useful Improvement in Grank S'hafts,0f which the following is a specification.-

My invention relates to the balancing of crank-shafts by means of counterbalancingdisks secured to the cranks in the planes thereof; and the object of the invention is to tion through the centerof the by a plane coinciding with the axis of the provide a better means for fitting and securing said disks to the cranks, whereby the former may be readily taken off the latter when necessary and replaced without refitting, the seat or bearing of the disk upon thecrank and the fastening for the disk being such that said disk,when replaced after being taken off, shall run true and be concentric with the journals of the shaft.

This improved means for balancing cranks is applicable whether there are one,0r more cranks upon the same shaft, and withou t regard to the angle they make with each other, or whether the cut throw, each.

Referring to the drawings, Fi gnre 1 is an end view of a shaft, showing the crank and balancing-disk in side elevation, said disk being secured to place upon the crank; Fig. 2, aseccrank, and disk shaft',.taken as upon the dotted line ww in Fig. 1, and viewed as indicated by the arrow pointed thereon; and Fig. 3, a section of the parts taken through the center of the shaft at right angles to the section shown in Fig. 2, as I upon the dotted line 3 y'in Fig. 1, and viewed as indicated by the arrow pointed thereon. The remaining seven figures are drawn to show modifications in the manner of securing the 1 disk in place upon the crank.

Vreceivesaid crank, the said disk Referring to the-parts of the device, A is the shaft, 'B the crank, and G the wrist-pin,

all of which may be forgedor castin one piece".

0 is the balancing-disk, which, with the weighted part H, is castin one piece, and with an opening, 9, of sufficient size in which to being placed upon the crank so that the weight H shall be diametrically opposite the outer or free end of the crank. The part of the concave surface of the disk from a to b in'said openingg is bored ina lathe or otherwise truly formed concentric with the periphery of the disk. The corresponding convex surface of the crank is turned or fitted on a circle of the same radius as that of said concave surface of the disk concentric with the journals of the shaft, on account of which, when these two surfaces are brought together,the disk will run truly when the shaft is rotated.

F isa set-screw threaded within the periphery of the disk in a radial position midway between the bars E, at the sides of said opening the inner, end of pointed and caused to enter a conical cavity, '0, in the free end of the crank, by tightening which screw the trued surfaces of said crank and disk from a to b, above mentioned, are brought firmly together, the disk being thus cranks are of the same or diti'er-' a balancing-disk being fitted to rigidly secured to the crank, as shown. The disk, if properly proportioned, when thus held upon the crank, will balance the weight of the outer end of the latter with the wristpin and so much of the connecting-rod as is supported thereon, causing the whole to run smoothly:

To economize in time and labor in the matter of fitting the crank and disk together, as stated, and for another-purpose, hereinafter stated, the disk is formed with a circular concentric recess, e, between the points a and b, leaving only narrow bearing-surfaces 10 either side thereof, along which surfaces only there is actual contact between said crank and disk. The crank, where. it' covers said recess, is formed with a peripheral'tongue or projection, r, entering said recess, but not filling the latter, space being left in said recess; outside of said projectionr to receive afillipg, as of soft metal poured in through a hole, f, or entered in some other manner. The cavityeis formed by the usual process of coring, and the filling fits snugly against the walls thereof and the edges or shoulders of the projection r of the crank,efl'ectually preventing longitudinal motion of the disk upon the crank. Grooves'or openings of other form maybe cut in this part of the crank to receive the filling, in addition to or without the projection r,or other means which screw being used to increase the hold of the filling uponthe crank. If desired, the entire weighted portion H of the disk may be cored out in casting, as indicated in dotted lines, and the whole filled with lead, thereby increasing the weight.

Other fasteners for the disk and crank than the threaded bolt F, above mentioned, may be employed, judgment may determine, without further invention. For instance, as shown in Fig. 4, parallel studs or bolts h may be employed in place of the bars E on either side of the crank, threaded in the disk 0, and provided with a cap, j, to bear upon the free end of the crank,'-with screw-nuts on top of said cap.

in Fig. 5 a fastener is shown in the form of a buggy-clip passing around the end of the crank, with threaded ends extending through parts of the disk and provided with screwnuts resting in cavities in said disk. Bytightening said screw-nuts the disk will be firmly fastened to the crank.

Fig. 6 shows a cross-key, m, insertedin mortises formed in the bars E in position to bear upon the hub of the crank, by tightening which key the parts will be bound together,as before. A small set-screw may be provided to secure the key in place in the ordinary manner.

Fig. 7 shows a form of buggy-clip bearing upon the end of the crank formed with lateral lugs k, through which short tightening-bolts h pass, threaded in the disk 0, and Fig. 8 shows a short stout stud, a, threaded in the crank or shaft, and reaching radially through a portion of the disk into a cavity therein containing a screw-nut. By tightening said nut the disk will be firmly held to the crank.

Counterbalancing-disks have been used upon cranks before my application for a patent of which this is the specification; but, so far as I am aware, such disks have been secured to the cranks rigidly and are not detachable. Frequently the wrist-pin and the journals of the shaft become worn and have to be re-formed in a lathe, in which case it becomes exceedingly desirable to remove the balancing-disk from the crank, as with it off the shaft can be much more conveniently handled, and, besides, the worn parts can be returned in a much smaller lathe. The importance of my invention rests mainly in the fact that the balancing-disk may be removed from the crank at any time and as often as may be desired, and replaced without having to be refitted, the fitting and fastening being such that said disk will come back to its exact place at each time when replaced and run evenly as when first fitted; also, the disks are firmly held to the cranks and with less weight of parts than is the case with others now in use.

\Vhat I claim as my invent-ion is- 1. A shaft provided with a crank,.the latter having its end attached to said shaft formed into a circular seat concentric with the journals of the shaft, in combination with a disk formed with an opening in which to receive the crank, the interior surface'at one end of said opening being formed into a circular seat concentric with the periphery of the disk, said circular seat of the disk having the same radius as said seat of the crank, to the end that said two seats shall touch and bear evenly togcther when the disk is'placed upon the crank, and a fastener for the disk and crank, substantially as shown and described.

2. A shaft provided with a crank, the latter having its end nearest said shaft formed into a circular scat or bearing concentric with thejournals of the shaft, in combination with a disk formed with an opening in which to receive the crank,.the interior surface at one end of said opening being formed into a circular seat or hearing concentric with the periph ery of the disk, said circular seat of the disk being formed of the same radius as said seat of the crank, to the end that said two seats shall touch and bear evenly when the disk is in place upon the crank, said circular seat or bearing of the diskt having a recess, and the contiguous surface ofithe crank having a raised part to enter said recess, and a fastener for the disk and crank, substantially as shown and described.

3. A crank-shaft and crank, the latter having a portion of its convex surface formed concentric with the journals of the shaft, in combination with a balancing-disk for said crank formed with a concave surface to fit said convex concentric surface of the crank, said concave surface having a recess, and the opposing surface of said crank having a raised part to enter said recess without filling the latter, said recess outside of said raised part being filled by another substance, and a fastener for said crank and disk, substantially as shown and described.

D. A. \VOODBURY.

Witnesses:

HENRY B. HOWE,

J. \VAYLAND CLARK. 

